Melena: Causes, Risk Factors, Symptoms, Diagnosis, Treatment and Prognosis

It is a form of bleeding from the digestive system.

It is then the evacuation of black stools due to the blood content.

This type of gastrointestinal bleeding results in an expulsion of blood from the digestive system: the digestive tract, the bile ducts or even the pancreas.

Furthermore, upper hemorrhages, originating in the upper part of the duodenojejunal angle, must be distinguished from low hemorrhages (originating below this angle).

The melena is then a low hemorrhage, and in most cases it comes from a hemorrhage in the right corner of the colon.

The causes of the mane

The main reason for developing melena is bleeding, which can start anywhere in the digestive tract, but most often to pathology, leading to the stomach ulcer, the duodenum.

At the onset of bleeding can lead to peptic ulcers, tumors, diverticula, polyps.

In rare cases, black stools occur with diseases of the pancreas or gallbladder.

In childhood, black stools may be associated with Meckel’s protrusion (congenital or acquired pathology of intestinal development).

In addition to internal causes, the disorder can lead to certain medications, bleeding disorders, lung or nose bleeding (in this case, the person swallows the blood that enters the stomach).

Different causes can give rise to a mane:

  • The presence of a polyp (growth of the intestinal mucosa) or cancer.
  • Diverticular bleeding (caused by small hernias formed in the intestinal wall).
  • Ischemic, infectious, inflammatory, or radiological colitis.
  • A rectal ulcer (especially in the elderly).
  • Hemorrhage caused by hemorrhoids

In rare cases, melena can arise from angiodysplasias, tumors, and ulcerations from non-steroidal anti-inflammatory drugs.

Mane risk factors

People who suffer from disorders in the digestive system have a greater risk of contracting melena (gastric or intestinal ulcer, ischemic colitis, etc.).

In addition, patients of geriatric age are at greater risk of melena.

The symptoms

The mane in case of extensive hemorrhage manifests a liquid stool.

If there is no excessive bleeding, the stool is black in color and retains its shape after defecation.

With an addiction to constipation, the disorder can manifest itself 2-3 days after the bleeding begins.

In most cases, the condition has symptoms that are not related to bleeding: tinnitus, weakness, nausea, loss of consciousness, darkening of the eyes, hot or cold sweats, paleness.

Usually these symptoms appear before melena.

If the loss of blood from the body less than 500 ml, the disorder occurs without clearly marked symptoms of blood loss.

But when it is approximately 1L, there may be possible changes in blood pressure, in the pulse.

Higher blood losses can cause hemorrhagic shock, greatly reduced pressure, loss of consciousness, reduced or total absence of reflexes.

The clinical signs of melena result in:

  • The emission of black blood, accompanied by a fetid odor, in the stool.
  • An intestinal pain.


The mane is first detected during the fecal examination of the patient.

However, if the stool is not present in the stool examination, the patient’s diet should be taken into account.

The darkening of the stool can be due to the use of certain products such as blueberries, red wine, beets, as well as due to certain medications, especially iron, in which case they have a characteristic for the shine of the mane.

A nasogastric lavage can be done to find out if the bleeding is in the upper or lower digestive tract.

Colonoscopy is used to look for the source of bleeding, it can also be used to collect small samples for biopsies.

The diagnosis of the disease is confirmed or reversed after endoscopy.


The management of the treatment of low hemorrhages depends on the origin of these.

It can be a simple therapeutic treatment, an endoscopic ablation or a particular diet to follow. But it can also be a medical emergency.

The doctor will prescribe or recommend a treatment according to the diagnosis, in the case of stomach ulcers caused by non-steroidal anti-inflammatory drugs, these heal when the drug that causes them is stopped.

There are some natural medicine studies that recommend the use of licorice, nopal, cruciferous, cranberry juice, apricot and honey for inflammations, gastric and duodenal ulcers.


In most cases, the disorder is caused by severe internal bleeding, which requires urgent medical intervention.

The mane, in addition to bleeding, can cause disability and even cause death.

The predictions depend on the timely detection of the pathology and a set of therapeutic measures to eliminate it.

The melena or black stools is a pathological condition in which black stools are secreted due to the presence of blood in the stomach, altered by the action of gastric juice.